1 /* Freescale S12Z-specific support for 32-bit ELF
2    Copyright (C) 1999-2021 Free Software Foundation, Inc.
3    (Heavily copied from the D10V port by Martin Hunt (hunt@cygnus.com))
4 
5    This file is part of BFD, the Binary File Descriptor library.
6 
7    This program is free software; you can redistribute it and/or modify
8    it under the terms of the GNU General Public License as published by
9    the Free Software Foundation; either version 3 of the License, or
10    (at your option) any later version.
11 
12    This program is distributed in the hope that it will be useful,
13    but WITHOUT ANY WARRANTY; without even the implied warranty of
14    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
15    GNU General Public License for more details.
16 
17    You should have received a copy of the GNU General Public License
18    along with this program; if not, write to the Free Software
19    Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston,
20    MA 02110-1301, USA.  */
21 
22 #include "sysdep.h"
23 #include "bfd.h"
24 #include "bfdlink.h"
25 #include "libbfd.h"
26 #include "elf-bfd.h"
27 
28 #include "elf/s12z.h"
29 
30 /* All users of this file have bfd_octets_per_byte (abfd, sec) == 1.  */
31 #define OCTETS_PER_BYTE(ABFD, SEC) 1
32 
33 /* Relocation functions.  */
34 static reloc_howto_type *bfd_elf32_bfd_reloc_type_lookup
35   (bfd *, bfd_reloc_code_real_type);
36 static bool s12z_info_to_howto_rel
37   (bfd *, arelent *, Elf_Internal_Rela *);
38 
39 static bfd_reloc_status_type
opru18_reloc(bfd * abfd,arelent * reloc_entry,struct bfd_symbol * symbol,void * data,asection * input_section ATTRIBUTE_UNUSED,bfd * output ATTRIBUTE_UNUSED,char ** msg ATTRIBUTE_UNUSED)40 opru18_reloc (bfd *abfd, arelent *reloc_entry, struct bfd_symbol *symbol,
41 		    void *data, asection *input_section ATTRIBUTE_UNUSED,
42 		    bfd *output ATTRIBUTE_UNUSED, char **msg ATTRIBUTE_UNUSED)
43 {
44   /* This reloc is used for 18 bit General Operand Addressing Postbyte in the
45      INST opru18 form.  This is an 18 bit reloc, but the most significant bit
46      is shifted one place to the left of where it would normally be.  See
47      Appendix A.4 of the S12Z reference manual.  */
48 
49   bfd_size_type octets = (reloc_entry->address
50 			  * OCTETS_PER_BYTE (abfd, input_section));
51   bfd_vma result = bfd_get_24 (abfd, (unsigned char *) data + octets);
52   bfd_vma val = bfd_asymbol_value (symbol);
53 
54   /* Keep the wanted bits and discard the rest.  */
55   result &= 0xFA0000;
56 
57   val += symbol->section->output_section->vma;
58   val += symbol->section->output_offset;
59 
60   /* The lowest 17 bits are copied verbatim.  */
61   result |= val & 0x1FFFF;
62 
63   /* The 18th bit is put into the 19th position.  */
64   result |= (val & 0x020000) << 1;
65 
66   bfd_put_24 (abfd, result, (unsigned char *) data + octets);
67 
68   return bfd_reloc_ok;
69 }
70 
71 
72 static bfd_reloc_status_type
shift_addend_reloc(bfd * abfd,arelent * reloc_entry,struct bfd_symbol * symbol ATTRIBUTE_UNUSED,void * data ATTRIBUTE_UNUSED,asection * input_section ATTRIBUTE_UNUSED,bfd * output ATTRIBUTE_UNUSED,char ** msg ATTRIBUTE_UNUSED)73 shift_addend_reloc (bfd *abfd, arelent *reloc_entry, struct bfd_symbol *symbol ATTRIBUTE_UNUSED,
74 		    void *data ATTRIBUTE_UNUSED, asection *input_section ATTRIBUTE_UNUSED,
75 		    bfd *output ATTRIBUTE_UNUSED, char **msg ATTRIBUTE_UNUSED)
76 {
77   /* This is a really peculiar reloc, which is done for compatibility
78      with the Freescale toolchain.
79 
80      That toolchain appears to (ab)use the lowest 15 bits of the addend for
81      the purpose of holding flags.  The purpose of these flags are unknown.
82      So in this function, when writing the bfd we left shift the addend by
83      15, and when reading we right shift it by 15 (discarding the lower bits).
84 
85      This allows the linker to work with object files generated by Freescale,
86      as well as by Gas.  */
87 
88   if (abfd->is_linker_input)
89     reloc_entry->addend >>= 15;
90   else
91     reloc_entry->addend <<= 15;
92 
93   return bfd_reloc_continue;
94 }
95 
96 #define USE_REL	0
97 
98 static reloc_howto_type elf_s12z_howto_table[] =
99 {
100   /* This reloc does nothing.  */
101   HOWTO (R_S12Z_NONE,	/* type */
102 	 0,			/* rightshift */
103 	 3,			/* size (0 = byte, 1 = short, 2 = long) */
104 	 0,			/* bitsize */
105 	 false,			/* pc_relative */
106 	 0,			/* bitpos */
107 	 complain_overflow_dont,/* complain_on_overflow */
108 	 bfd_elf_generic_reloc,	/* special_function */
109 	 "R_S12Z_NONE",	/* name */
110 	 false,			/* partial_inplace */
111 	 0,			/* src_mask */
112 	 0,			/* dst_mask */
113 	 false),		/* pcrel_offset */
114 
115   /* A 24 bit absolute relocation emitted by the OPR mode operands  */
116   HOWTO (R_S12Z_OPR,        /* type */
117 	 0,			/* rightshift */
118 	 5,			/* size (0 = byte, 1 = short, 2 = long) */
119 	 24,			/* bitsize */
120 	 false,			/* pc_relative */
121 	 0,			/* bitpos */
122 	 complain_overflow_bitfield,	/* complain_on_overflow */
123 	 shift_addend_reloc,
124 	 "R_S12Z_OPR",	/* name */
125 	 false,			/* partial_inplace */
126 	 0x00ffffff,            /* src_mask */
127 	 0x00ffffff,		/* dst_mask */
128 	 false),		/* pcrel_offset */
129 
130   /* The purpose of this reloc is not known */
131   HOWTO (R_S12Z_UKNWN_2,	/* type */
132 	 0,			/* rightshift */
133 	 3,			/* size (0 = byte, 1 = short, 2 = long) */
134 	 0,			/* bitsize */
135 	 false,			/* pc_relative */
136 	 0,			/* bitpos */
137 	 complain_overflow_dont,/* complain_on_overflow */
138 	 bfd_elf_generic_reloc,	/* special_function */
139 	 "R_S12Z_UKNWN_2",	/* name */
140 	 false,			/* partial_inplace */
141 	 0,			/* src_mask */
142 	 0,			/* dst_mask */
143 	 false),		/* pcrel_offset */
144 
145   /* A 15 bit PC-rel relocation */
146   HOWTO (R_S12Z_PCREL_7_15,	/* type */
147 	 0,			/* rightshift */
148 	 1,			/* size (0 = byte, 1 = short, 2 = long) */
149 	 15,			/* bitsize */
150 	 true,			/* pc_relative */
151 	 0,			/* bitpos */
152 	 complain_overflow_bitfield,	/* complain_on_overflow */
153 	 shift_addend_reloc,
154 	 "R_S12Z_PCREL_7_15",	/* name */
155 	 false,			/* partial_inplace */
156 	 0x00,                  /* src_mask */
157 	 0x007fff,		/* dst_mask */
158 	 true),			/* pcrel_offset */
159 
160   /* A 24 bit absolute relocation emitted by EXT24 mode operands */
161   HOWTO (R_S12Z_EXT24,        /* type */
162 	 0,			/* rightshift */
163 	 5,			/* size (0 = byte, 1 = short, 2 = long) */
164 	 24,			/* bitsize */
165 	 false,			/* pc_relative */
166 	 0,			/* bitpos */
167 	 complain_overflow_bitfield,	/* complain_on_overflow */
168 	 bfd_elf_generic_reloc,	/* special_function */
169 	 "R_S12Z_EXT24",	/* name */
170 	 false,			/* partial_inplace */
171 	 0x00000000,            /* src_mask */
172 	 0x00ffffff,		/* dst_mask */
173 	 false),		/* pcrel_offset */
174 
175   /* An 18 bit absolute relocation */
176   HOWTO (R_S12Z_EXT18,        /* type */
177 	 0,			/* rightshift */
178 	 5,			/* size (0 = byte, 1 = short, 2 = long) */
179 	 18,			/* bitsize */
180 	 false,			/* pc_relative */
181 	 0,			/* bitpos */
182 	 complain_overflow_bitfield,	/* complain_on_overflow */
183 	 opru18_reloc,	        /* special_function */
184 	 "R_S12Z_EXT18",	/* name */
185 	 false,			/* partial_inplace */
186 	 0x00000000,            /* src_mask */
187 	 0x0005ffff,		/* dst_mask */
188 	 false),		/* pcrel_offset */
189 
190   /* A 32 bit absolute relocation.   This kind of relocation is
191      schizophrenic - Although they appear in sections named .rela.debug.*
192      in some sections they behave as RELA relocs, but in others they have
193      an added of zero and behave as REL.
194 
195      It is not recommended that new code  emits this reloc.   It is here
196      only to support existing elf files generated by third party
197      applications.  */
198 
199   HOWTO (R_S12Z_CW32,        /* type */
200 	 0,			/* rightshift */
201 	 2,			/* size (0 = byte, 1 = short, 2 = long) */
202 	 32,			/* bitsize */
203 	 false,			/* pc_relative */
204 	 0,			/* bitpos */
205 	 complain_overflow_bitfield,	/* complain_on_overflow */
206 	 bfd_elf_generic_reloc,	/* special_function */
207 	 "R_S12Z_CW32",	/* name */
208 	 false,			/* partial_inplace */
209 	 0xffffffff,            /* src_mask */
210 	 0xffffffff,		/* dst_mask */
211 	 false),		/* pcrel_offset */
212 
213   /* A 32 bit absolute relocation  */
214   HOWTO (R_S12Z_EXT32,        /* type */
215 	 0,			/* rightshift */
216 	 2,			/* size (0 = byte, 1 = short, 2 = long) */
217 	 32,			/* bitsize */
218 	 false,			/* pc_relative */
219 	 0,			/* bitpos */
220 	 complain_overflow_bitfield,	/* complain_on_overflow */
221 	 bfd_elf_generic_reloc,	/* special_function */
222 	 "R_S12Z_EXT32",	/* name */
223 	 false,			/* partial_inplace */
224 	 0x00000000,            /* src_mask */
225 	 0xffffffff,		/* dst_mask */
226 	 false),		/* pcrel_offset */
227 };
228 
229 /* Map BFD reloc types to S12Z ELF reloc types.  */
230 
231 struct s12z_reloc_map
232 {
233   bfd_reloc_code_real_type bfd_reloc_val;
234   unsigned char elf_reloc_val;
235 };
236 
237 static const struct s12z_reloc_map s12z_reloc_map[] =
238 {
239   /* bfd reloc val */  /* elf reloc val */
240   {BFD_RELOC_NONE,     R_S12Z_NONE},
241   {BFD_RELOC_32,       R_S12Z_EXT32},
242   {BFD_RELOC_24,       R_S12Z_EXT24},
243   {BFD_RELOC_16_PCREL, R_S12Z_PCREL_7_15},
244   {BFD_RELOC_S12Z_OPR, R_S12Z_OPR}
245 };
246 
247 static reloc_howto_type *
bfd_elf32_bfd_reloc_type_lookup(bfd * abfd ATTRIBUTE_UNUSED,bfd_reloc_code_real_type code)248 bfd_elf32_bfd_reloc_type_lookup (bfd *abfd ATTRIBUTE_UNUSED,
249 				 bfd_reloc_code_real_type code)
250 {
251   unsigned int i;
252 
253   for (i = 0;
254        i < sizeof (s12z_reloc_map) / sizeof (struct s12z_reloc_map);
255        i++)
256     {
257       if (s12z_reloc_map[i].bfd_reloc_val == code)
258 	{
259 	  return &elf_s12z_howto_table[s12z_reloc_map[i].elf_reloc_val];
260 	}
261     }
262 
263   printf ("%s:%d Not found type %d\n", __FILE__, __LINE__, code);
264 
265   return NULL;
266 }
267 
268 static reloc_howto_type *
bfd_elf32_bfd_reloc_name_lookup(bfd * abfd ATTRIBUTE_UNUSED,const char * r_name)269 bfd_elf32_bfd_reloc_name_lookup (bfd *abfd ATTRIBUTE_UNUSED,
270 				 const char *r_name)
271 {
272   unsigned int i;
273 
274   for (i = 0;
275        i < (sizeof (elf_s12z_howto_table)
276 	    / sizeof (elf_s12z_howto_table[0]));
277        i++)
278     if (elf_s12z_howto_table[i].name != NULL
279 	&& strcasecmp (elf_s12z_howto_table[i].name, r_name) == 0)
280       return &elf_s12z_howto_table[i];
281 
282   return NULL;
283 }
284 
285 /* Set the howto pointer for an S12Z ELF reloc.  */
286 
287 static bool
s12z_info_to_howto_rel(bfd * abfd,arelent * cache_ptr,Elf_Internal_Rela * dst)288 s12z_info_to_howto_rel (bfd *abfd,
289 			  arelent *cache_ptr, Elf_Internal_Rela *dst)
290 {
291   unsigned int  r_type = ELF32_R_TYPE (dst->r_info);
292 
293   if (r_type >= (unsigned int) R_S12Z_max)
294     {
295       /* xgettext:c-format */
296       _bfd_error_handler (_("%pB: unsupported relocation type %#x"),
297 			  abfd, r_type);
298       bfd_set_error (bfd_error_bad_value);
299       return false;
300     }
301 
302   cache_ptr->howto = &elf_s12z_howto_table[r_type];
303   return true;
304 }
305 
306 static bool
s12z_elf_set_mach_from_flags(bfd * abfd)307 s12z_elf_set_mach_from_flags (bfd *abfd)
308 {
309   bfd_default_set_arch_mach (abfd, bfd_arch_s12z, 0);
310 
311   return true;
312 }
313 
314 #define ELF_ARCH		bfd_arch_s12z
315 #define ELF_MACHINE_CODE	EM_S12Z
316 #define ELF_MAXPAGESIZE		0x1000
317 
318 #define TARGET_BIG_SYM		s12z_elf32_vec
319 #define TARGET_BIG_NAME		"elf32-s12z"
320 
321 #define elf_info_to_howto			NULL
322 #define elf_info_to_howto_rel			s12z_info_to_howto_rel
323 #define elf_backend_object_p			s12z_elf_set_mach_from_flags
324 
325 #include "elf32-target.h"
326